Solid state positive force touch sensing

Abstract

A touch sensor pad, including a touch sensor that senses the presence of a touching member placed proximate the touch sensor. A layer of protective material overlies the touch sensor. The layer of protective material has a first surface proximate the touch sensor and an opposing second surface distal from the touch sensor. The second surface includes a resting surface portion and a developed surface portion. The developed surface portion is recessed below the resting surface portion such that the developed surface portion is nearer to the touch sensor than the resting surface portion. The touch sensor has a sensitivity such that the presence of a touching member in contact with the resting surface portion does not result in an actuation of the touch sensor while the presence of a touching member pressed into the developed surface portion does result in the actuation of the touch sensor.

1 . A touch sensor pad, comprising:
 a touch sensor that senses the presence of a touching member placed proximate the touch sensor;   a layer of protective material overlying the touch sensor, the layer of protective material having a first surface proximate the touch sensor and an opposing second surface distal from the touch sensor;   the second surface including a resting surface portion and a developed surface portion, the developed surface portion being recessed below the resting surface portion such that the developed surface portion is nearer to the touch sensor than the resting surface portion; and   the touch sensor having a sensitivity such that the presence of a touching member in contact with the resting surface portion does not result in an actuation of the touch sensor while the presence of a touching member pressed into the developed surface portion does result in the actuation of the touch sensor.   
     
     
         2 . The touch sensor pad as claimed in  claim 1 , wherein the developed surface portion includes structure that provides tactile feedback when the touching member is a finger and the finger is pressed into the developed surface portion. 
     
     
         3 . The touch sensor pad as claimed in  claim 2 , wherein the structure that provides tactile feedback comprises a raised portion within the developed surface portion. 
     
     
         4 . The touch sensor pad as claimed in  claim 3 , wherein the raised portion presents a dome shaped surface. 
     
     
         5 . A touch sensor pad, comprising:
 a touch sensor that senses the presence of a touching member placed proximate the touch sensor, the touch sensor having a sensitivity range extending outwardly therefrom wherein a touch from the touching member within the sensitivity range results in an actuation and a touch from the touching member outside the sensitivity range does not result in actuation;   a layer of protective material overlying the touch sensor, the layer of protective material having a first surface proximate the touch sensor and an opposing second surface distal from the touch sensor; and   the second surface including a resting surface portion and a developed surface portion, the resting surface portion being located outside of the sensitivity range and the developed surface portion being recessed from the resting surface portion and located at least partially within the sensitivity range of the touch sensor.   
     
     
         6 . The touch sensor pad as claimed in  claim 5 , wherein the developed surface portion includes structure that provides tactile feedback when the touching member is a finger and the finger is pressed into the developed surface portion. 
     
     
         7 . The touch sensor pad as claimed in  claim 6 , wherein the structure that provides tactile feedback comprises a raised portion within the developed surface portion. 
     
     
         8 . The touch sensor pad as claimed in  claim 7 , wherein the raised portion presents a dome shaped surface. 
     
     
         9 . A method of distinguishing between an affirmative touch and an unintended touch in actuation of a touch sensor pad, comprising:
 presenting a touch sensor pad including a touch sensor that senses the presence of a touching member placed proximate the touch sensor, the touch sensor having a sensitivity range extending outwardly therefrom wherein a touch from the touching member within the sensitivity range results in an actuation and the a touch from the touching member outside the sensitivity range does not result in actuation;   covering the touch sensor with a layer of protective material, the layer of protective material having a first surface proximate the touch sensor and an opposing second surface distal from the touch sensor;   structuring the second surface to include a resting surface portion and a developed surface portion, the developed surface portion being recessed from the resting surface portion; and   adjusting or selecting the touch sensor pad such that the resting surface portion is located outside of the sensitivity range and the developed surface portion is located at least partially within the sensitivity range of the touch sensor.   
     
     
         10 . The method as claimed in  claim 9  further comprising structuring the developed surface portion to include structure that provides tactile feedback when the touching member is a finger and the finger is pressed into the developed surface portion. 
     
     
         11 . The method as claimed in  claim 10 , further comprising shaping the structure that provides tactile feedback to comprise a raised portion within the developed surface portion. 
     
     
         12 . The method as claimed in  claim 11 , further comprising shaping the raised portion to present a dome shaped surface. 
     
     
         13 . A method of using a touch sensor pad, comprising:
 resting a fingertip on a resting portion of a proximal surface of a layer of protective material overlying a touch sensor and proximal to a developed surface portion of the proximal surface,   when it is desired to actuate the touch sensor, pressing the fingertip against the proximal surface of until the fingertip deforms and a deformed portion of the fingertip enters a developed surface portion of the proximal surface thereby placing the portion of the fingertip at least partially within a sensitivity range extending outwardly from the touch sensor wherein the presence of the portion of the fingertip within the sensitivity range results in an actuation; and   releasing pressure on the fingertip thereby removing the deformed portion from within the sensitivity range of the touch sensor wherein the absence of the portion of the fingertip within the sensitivity range ends the actuation.   
     
     
         14 . The method as claimed in  claim 13  further comprising pressing the deformed portion of the fingertip until it touches a structure within the developed surface that provides tactile feedback and perceiving the tactile feedback prior to the releasing pressure on the fingertip.